She swaggered onstage in knee-length boots, hip-hugging breeches, silk-lined cloak and tricorn hat – the epitome of a pantomime principal boy.

This was perfectly appropriate for a concert of music from her album Sacrificium which explores works performed by opera’s most exotic performers, the castrati, who combined glorious singing with gender-bending and a dash of theatrical camp.

Apart from Handel, the 18th century composers whose music Bartoli brought so vividly to life – Broschi, Caldara, Araia – are now just footnotes in books of musical scholarship. She has unearthed some operatic gems, lavished upon them all her prodigious vocal talents and presented them with immense vivacity. Nicolo Porpora’s storm aria Como nave got us under way emphatically but his gentle Usignola sventurato, complete with bird calls and piccolo accompaniment, saw Bartoli create a hushed mood of pastoral repose.

The Kammerorchester Basel, under their exuberant leader Julia Schröder, gave splendid support both in the arias and the interspersed instrumental pieces by Porpora.

Castrati also sang female roles and for Porpora’s florid and rousing Nobil onda Bartoli donned crinoline flounces and ostrich feathers – both diva and divo. Bartoli’s singing, her beaming smile and showmanship reminds us that opera can be fun – her standing ovation was thoroughly deserved.

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